Apart from being mis-titled for North American readers, this is a mind-expanding view of "what's out there" - or might be. Released as "Evolving the Alien" in the UK, this book examines numerous and too often poorly considered suggestions about how life might evolve in other places. Note "places," since Cohen and Stewart don't limit their conjectures to planets alone. Noting the impact of H.G. Wells' "War of the Worlds" as a starting point for how we think about life elsewhere, Cohen and Stewart divide the book between evidence from hard science and the conjectures of "SF" [speculative fiction] authors. Including themselves. In their view, both exobiologists and novelists have been remiss in considering how alien life might evolve. They do a comprehensive job, presented with the kind of wit expected of collaborators of Terry Pratchett of Discworld fame. Recognizing they are entering a relatively unexplored area, they abandon old terms like "astrobiology" or "extraterrestrial life" to suggest a new, all encompassing term - xenobiology. They condemn outright the narrow views expressed by some scientists, notably Peter Ward and Donald Brownlee in "Rare Earth." Cohen and Stewart argue that limiting life to DNA-based forms is far too restrictive. Different environments are capable of producing life in ways "we can't even imagine." Magnetic fields in suns or neutron stars, silicon-based chemistry, unusual energy uses are all part of the panorama nature has in its recipes in making life start. Our localized experience is too limited, they argue, and we should look further with more open minds. Those who have attempted a more open view have traditionally been limited to writers of speculative fiction. Cohen and Stewart sprinkle the text with examples of this genre, accompanied by an analysis of what is right or wrong with the ET life presented. "Science fiction" might just as easily be labelled "fictional science" in the eyes of these authors. Too little attention has been given to environmental complexity by the legions of writers seeking to entertain readers with simple plots and much action. Among that phalanx, however, there are some writers who strive to bring reality to the fictional worlds they create. Jack Cohen has been called into the story-building process as a consultant by several authors. The result, once the dust had settled, was SF with a reality check. The authors give accounts of some of these efforts and the resulting books should be sought out and compared to those less favoured by the authors of this book. Jack&Ian [as they style themselves] have provided a rich trove of ideas for nearly everyone. Scientists can gain fresh areas of research to consider, while fiction readers may find a whole new list of interesting readings. The book isn't footnoted, but there is a divided bibliography of "Popular Xenoscience Reading" and "Technical Xenoscience Reading" at the end. If you fail to find new concepts to consider here, you haven't tried.
Jack Cohen and Ian Stewart are interesting thinkers and writers in the guise of Jack&Ian, and What Does A Martian Look Like? is a very good, thought provoking read. This book takes an optomistic view of the possibilities of life and intelligence elsewhere in the universe and proposes a broad xenoscience as an antidote to what Jack&Ian see as the narrow view of astrobiology. Rare Earth by Peter Ward and Donald Brownlee comes in for the most criticism [not for the writing, but for the opinions], being one of the most popular books on astrobiology in the last few years. Stewart and Cohen do their best when they discuss their ideas in the context of science fiction stories and hit bottom when their criticisms of mainstream astrobiology begin to sound petty. Fans of mainstream SF should be prepared for the dressing down of their favorite aliens. If it'll hurt your feelings to find out that aliens probably won't look humanoid, do not read this book. Although not a perfect book, What Does A Martin Look Like? [especially if paired with the book Rare Earth] will take the reader's thinking to the far corners of the universe.
Setting aside that the authors take an unfair swipe at the Waldahudin from my Hugo Award-nominated STARPLEX as being too like Earthly fauna (getting their facts wrong while doing so, and not discussing the very alien Darmats [dark-matter aliens] and Ibs [gestalt organisms] from that novel), this is still a pretty good book, although the dogmatic tone gets tiresome awfully fast. In a way, Stewart and Cohen should be praised for using so many examples from science fiction, but, at the same time, they give very short shrift to the notion that some SF writers might be using aliens for literary/metaphoric purposes, rather than just as high-school-biology-class exercises in designing lifeforms. Stanley Schmidt's ALIENS AND ALIEN SOCIETIES is a better book (even if Stewart and Cohen's acknowledgement of its existence seems mostly limited to a petty critique of its cover art, incidentally -- although they don't mention this -- by Hugo Award-winner Bob Eggleton).